A fixing device includes a fixing member, at least one temperature detector, and a device-side drawer connector. The at least one temperature detector is configured to detect a temperature of the fixing member, the at least one temperature detector including a plurality of lead wires. The device-side drawer connector has a terminal portion configured to fit with a terminal portion of a body-side drawer connector of an image forming apparatus body to connect the plurality of lead wires of the at least one temperature detector to the image forming apparatus body. The device-side drawer connector is configured to branch a signal wire of the plurality of lead wires of the at least one temperature detector into a plurality of systems. A plurality of earth wires of the plurality of lead wires of the at least one temperature detector is short-circuited to each other.